Vibrator circuit



Jan. 25, 1949. H. J. BROWN EI'AL VIBRATOR G IRCUIT INVENTORS Filed Nov. 26, 1943 A/MAL W 14.77211 VIBRATOR CIRCUIT Harold J. Brown and Joseph A. Mac, Indianapolis, Ind., assign on to Electronic Laboratories, Inc., a corporation of Indiana Application November 2c, 1943, Serial No. 511,782

The present invention relates to improvements in vibratory interrupters and more particularly to the circuit for energizing the coil of the driving magnet.

In certain types of vibratory interrupters, particularly those designed for operating converters or inverters and designed to operate at extremely high frequency and wherein the vibrating contact means is driven by an electromagnet, the power required to operate the vibrating contact means has been found to be excessive. This is particularly so in certain types of small vibratory circuit interrupters operating at extremely high frequencies. It has been found that in some instances the power necessary for driving the vibratory contact means has been as great as the output of the converter or inverter.

It is one of the objects of the present invention to provide a driving circuit for the electromagnet driving the vibrating contact means of the interrupter by which the operating characteristic of the driving electromagnet of the interrupter may be greatly improved thereby reducing its current consumption.

Another object of the invention is the provision of a driving circuit for the driving magnet which will reduce materially the heating of the magnet during its operation.

More particularly, the invention relates to 7 of energizing the driving magnet both by alternating and unidirectional current of substantially the same value through the vibrating contacts which govern the energizaticn of the transformer of the vibratory system.

Another object of our invention is the provision of a shunting circuit which is governed by the contact means that controls the energization of the transformer of the vibratory system, the shunting circuit upon the closing of the contact means shunting the driving 'magnet from the direct current source while at the same time 6 Claims. (01. -385) introducing in the shunting circuit an alternating current which opposes the unidirectional current to de-magnetize the driving magnet.

Other objects and a fuller understanding of our invention may be had by referring to the following description and claims, taken in combination with the accompanying drawing, in which:

Figure 1 is a diagrammatic view of a vibratory interrupter embodying the features of our invention;

Figure 2 is a diagrammatic view of a modification of our invention;

Figure 3 is a further modification of our invention; and

Figure 4 is a fragmentary view of a portion of our invention and shows the vibrating member constrained to engage one of the oppositely disposed contact members.

With reference to the drawing, and particularly to Figure 1, we provide a transformer i I having a split primary winding comprising two sections l2 and I3 and a secondary winding H. A primary winding is provided with a center tap connected to one side of the battery l0. While we have illustrated a source of battery current, it is to be understood that the source It may be any suitable unidirectional current source. The opposite side of the battery is connected through a switch i9 to a vibrating reed or member i5 of the vibratory interrupter. The vibrating reed i5 vibrates between a pair of oppositely disposed relatively stationary contacts is and II which are respectively connected through conductors 24 and 25 to the end terminals of the primary winding. A capacitor 20 may be connected across the two oppositely disposed stationary contacts i6 and ii.

For driving the vibrating member l5, we provide a driving magnet having a coil i8. As illustrated, the left-hand side of the coil i8 is connected through a conductor 23 to the vibrating member 5. The right-hand side of the coil I8 is connected through a conductor 22 to the upper end of an induction winding 2! which is associated with the core of the transformer H. The lower end of the induction winding 2| is connected to the upper end terminal of the primary winding of the transformer.

In operation, with the vibrating member 15 in a neutral position as shown in Figure 1, and with the switch l9 closed, a circuit is established for energizing the coil [8 of the driving magnet. This circuit may be referred to as a closed circuit and includes the battery it, the section it of 3 the primary winding, the winding 2|, the conductor 22, the coil l8 of the driving magnet, the conductor 23, and the switch l8, to the opposite side of the battery. Direct current will flow through the coil l8 of the driving magnet and will energize the magnet to move the vibrating member ill in a direction to engage the contact It. The instant that the vibrating member I5 engages the contact It, the coil It will be shunted from the battery II), in which event the battery ill will no longer supply direct current to the coil ll. However, the mere shunting of the coil it will not readily ,de-magnetize the driving magnet. Accordinzly, in our invention we include in the shunting circuit the induction winding 2| which induces an alternating current voltage in the shunting circuit which includes the induction winding 2|, the conductor 22, the coil It oi the driving magnet, the conductor 23, the vibrating member ii, the contact l6, and the conductor 24 to the opposite end of the induction winding 2|. The alternating current induced in the shunting circuit opposes the uni directional current flowing in the coil IS with the result that the driving magnet is readily de-magnetized. Upon thede-magnetization of the driving magnet. the vibrating member IE will swing in the opposite direction and make engagement with the contact I! which establishes a circuit for energizing the section |2 of the primary oi the transformer. Upon the energiza tion of the section 2 of the primary winding, the induction winding 2| will develop in the coil l8 a voltage and current in the same direction as that of the battery l0, thus providing driving current for the coil P8 of the driving magnet. In continuous operation, the coil i8 is energized by a modulating current which is composed of both alternating current and the interrupted direct current. We preferably make the modulating current such that it modulates from substantiaily zero to substantially twice its average value. In other words, the alternating and the direct current are substantially of the same value. in order to produce a modulated current in the coil i 8 which modulates from substantially zero to substantially twice its average value, the

- voltage produced in the winding 2| is greater than the voltage of the battery Hi. We have found that the ratio of the alternating current voltage to the direct current voltage impressed upon the coil i8 should be substantially equal to the ratio of the impedance of the coil to the resistance thereof to give the most satisfactory results. The current consumption required to energize the winding is is maintained at a low value and the heating thereof is greatly reduced.

In Figure 2- we show a modification of our invention in that the winding 2| is dispensed with and instead an alternating current voltage is introduced in the shunting circuit by employing a portion of the secondary winding ll. To this end, we connect the center tap of the primary winding to'an intermediate tap 26 upon the secondary winding. The conductor 22 may be connected to the upper end terminal of the secondary winding I'd. While we have illustrated the conductor 22 being connected to the upper In Figure 3 we show another modified form of our invention, in that the induction winding 21 takes the place of the winding 2| in Figure 1 and the secondary portion of the winding in Figure 2. In Figure 3, the upper terminal of the induction winding 21 is connected through the conductor 22 to the right-hand side of the coil i8 and the lower terminal of the induction winding 21 is connected to the center tap of the primary winding through the conductor 28. The operation of the circuit shown in Figure is substantially the same as that described with reference to Figure 1.

In Figure 4 we show the vibrating member l5 normally constrained to engage the contact Accordingly, upon the closing of the switch It the coil l8 of the driving magnetis instantly highly energized to give a quick starting action to the vibrating member IS. The modification shown in Figure 4 may be applied to any one of the circuits shown in Figures 1, 2 and 3. The sustained operation of the arrangement shown in Figure 4, when applied to the circuits shown in Figures 1, 2 and 3, is substantially the same so far as the operation is concerned as that here inbefore described with reference to the Figures 1, 2 and 3, respectively.

' Although we have described our invention with a certain degree of particularity, it is understood that the present disclosure has been made only by way of exampleand that numerous changes in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and the scope of the invention as hereinafter claimed.

:We claim as our invention:

1. In an electrical system for converting current from a direct current source into alternating current, a transformer having a core and a primary winding with opposite end terminals, oppositely disposed contact means respectively connected to the opposite end terminals of said primary winding, vibratory contact means disposed between said oppositely disposed contact means and connected to one side of the direct current source, a center tap for said primary winding connected to the opposite side of said direct current source, a driving magnet for said vibratory contact means, said driving magnet having a coil,

and circuit means for energizing the coil of the driving magnet, said circuit means comprising an induction winding surrounding the core of the transformer, said induction winding having a first and a second end connection, said first end connection being connected to an end terminal of the primary winding and said second end connection being connected to one side of the coil of the driving magnet, the other side of the coil of the driving magnet being connected to the vibratory contact means. 4

2. In an electrical system for converting current from a direct current source into alternating current, a, transformer having a core, having a secondary load winding and having a, primary winding with opposite end terminals, oppositely disposed contact means respectively connected to the opposite end terminals of said primary winding, vibratory contact means disposed between said oppositely disposed contact means and connected to one side of the direct current source, a center tap for said primary winding connected to the opposite side of said direct current source, a

7 driving magnet for said vibratory contact means,

said driving magnet having a coil, and circuit former including an induction winding surrounding the core or the transformer, said induction winding including at least a portion of said secondary load winding and having a first and a second end connection, said first end connection being connected to the primary winding and said second end connection being connected to one side of the coil of the driving magnet, the other side of the coil of the driving magnet being connected to the vibratory con-tact means.

3. In an electrical system for converting current from a direct current source into alternating current, a transformer having a core, a secondary load winding and a primary winding with opposite end terminals, oppositely disposed contact means respectively connected to the opposite end terminals of said primary winding, vibratory contact 'rneans disposed between said oppositely disposed contact means and connected to one side of a direct current source, a center tap for said primary winding connected to the opposite side of said direct current source, a driving magnet for said vibratory contact means, said driving magnet having a coil. and circuit means for energizing the coil of the driving magnet, said circuit means comprising, connection means for connecting the center tap of the primary winding to an intermediate point on the secondary winding, said secondary winding having a second point of a higher electrical potential than the intermediate point connected to one side of the coil of the driving magnet, the other side of the coil of the driving magnet being connected to the vibratory contact means.

4. A vibrator system including a transformer having primary and secondary load windings, said system providing a periodic voltage output obtained from a unidirectional voltage source as controlled by relatively movable vibrating contact means, a driver circuit for energizing a driver coil to cause vibration oi said vibrating contact means, said driver circuit including means controlled by said contact means for intermittently applying a given value of unidirectional voltage to said driver coil, said driver coil having given values of resistance and im-v pedance, said transformer including an inductive winding which includes a portion of one of said primary and secondary load windings for producing a periodic voltage therein, and means controlled by said contact means for intermittently applying to said driver coil from said inductive winding a value of periodic voltage having a ratio -relative to said unidirectional voltage substantially equal to the ratio of said given impedance and resistance.

5. In an electrical system comprising a vibratory interrupter, a transformer having primary and secondary load windings, at least one of said load windings having a control winding portion, said system having a driving magnet including a coil, means including contact means governed by the interrupter for intermittently applying a unidirectional current for energizing the coil of the driving magnet, and circuit means governed by the contact means to cause cessation of application of unidirectional current to the coil of the driving magnet, said transformer having an inductive winding including said control winding portion constituting a part of said circuit means for establishing in the circuit means an opposing current of substantially the same value as the unidirectional current to demagnetize the driving magnet.

6. An electrical system including an inductive winding, a vibratory interrupter having an output to said inductive winding and operated from a source of direct current and comprising oppositely disposed contact means and vibratory contact means therebetween, said inductive winding having a control winding portion, and circuit means including a driving coil intermittently energized from said source of direct current and controlled by said vibratory contact means and one of the oppositely disposed contact means for driving the vibratory contact means, said circuit means including said control winding portion for impressing upon the driving coil an alternating current voltage which is greater than the direct current voltage impressed upon the driving coil by the ratio of the inductive reactance to the resistance of the control winding portion.

HAROLD J. BROWN.

JOSEPH A. MAS.

REFERENCES CITED The following references are of record in the file of t:.ls patent:

UNITED STATES PATENTS Number Name Date 1,994,635 Cohen Mar. 19, 1935 2,066,995 Morack Jan. 5, 1937 2,156,708 Sullivan May 2, 1939 2,194,288 Aust Mar. 19, 1940 2,200,064 James May 7, 1940 2,265,717 Bedford Dec. 9, 1941 2,267,260 Alexander et al. Dec. 23, 1941 2,338,208 Shaver Jan. 4, 1944 

